[GSoC 2018] Expose subscribed webcal calendars via CalDAV

The calendar app has recently gained support for subscribing to third party webcal calendars. It would be great to expose these imported calendars via CalDAV (e.g. to mobile clients). Nextcloud would act as a kind of proxy service. One usecase is increased privacy for (mobile) users (only the Nextcloud server connection gets exposed to the original webcal provider).

For more details, have a look here

Feel free to ask for help if you want to get started with this topic!